1. Field of the Invention
The invention relates to a vehicle seat.
2. Description of Related Art
Japanese Patent Application Publication No. 2012-126167 (JP 2012-126167 A), for example, describes a vehicle seat that includes a slide mechanism for moving a seat main body on which a seated person is seated, forward and backward. The slide mechanism described in JP 2012-126167 A has a lower rail, an upper rail, and a plurality of balls. The lower rail is arranged on a vehicle structure member such as a floor of a vehicle. The lower rail is formed by a strip-shaped metal member that has been appropriately bent into an upwardly open cylindrical shape. The upper rail is formed by a strip-shaped metal member that has been appropriately bent so as to have a hat-shaped cross-section. The upper rail fits inside the lower rail. The plurality of balls are interposed between the upper rail and the lower rail. Here, the upper rail of the slide mechanism deforms by the input of an occupant load when the seated person is seated on the seat main body. The balls are pushed and moved with the deformation of the upper rail, and press on the inside surface of the lower rail. As a result, rattling of the lower rail and the upper rail is suppressed (rattling is inhibited).
However, the balls have a small diameter in order to be interposed in a gap between the lower rail and the upper rail. Therefore, it may be difficult to suitably suppress rattling of the lower rail and the lower rail at all of the balls. Also, the upper rail of the slide mechanism described above is inserted into the lower rail. Therefore, if the deformation from the input of the occupant load is large, the sliding resistance of the upper rail with respect to the lower rail will increase, and as a result, the upper rail may not slide smoothly. Consequently, the original function of the slide mechanism may be reduced.